Two-stroke internal-combustion engine



Filed March 30. 1925 .la 1 w 2 1 Z 5 par 1 w a. 4 A@ a K J Il Z l 1 x //////////////////////V 0o lIl. Ov n, n

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Patented Mar. 27, 1928.

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i EMILE-DUTEL, O 'F S'LfLAURENIE DU. VAR,y AND JEAN: MARC.,PERD`QNGINIOF NIZZA., FRANCE.v

TWO-STROKE' INTERNAL-CUMBUSTION ENGINE.

Application lecr'` Marclr- 3 0,- 1925', Serial The present invention relates Ato .two-stroke internal combustion engines` (as. distinct fromifourstroke engines with. torced induction, using the crank case compression for obtaining thenecessary air.pressure) of the passage.

`In internal combustion engines. ofi the above type it isscustomanyi toallow the pres-- sure produced.' ini the crank. case to` act uponv the fuel in the float# chamber 1n` order to equalize the pressurein y the float chamberJ and thel t-ransrferpassage.

Now. according t'o yourxinventi'on, the pressure obtaining in the fuel tank, as well as4 in the float chamber and in the transfer passage is equalized. by. providing a conduit from thexcrank. case tothe fueltank and a second pressure conduit from the top of the fuel tank to the top of the loat chamber, the usual fuel pipe being, of course, also provided between the fuel tank and the bottom of the float chamber. The pressure is also equalized between the cylinder and the other part-s when the transfer port is uncovered by the pist-on, so that a static equilibrium of pressure exists atv all times between the float chamber and the crank case and that, consequently, the spraying action of the nozzle takes place due to the suction of the working cylinder andthe dynamic depression caused by the flow of air around the nozzle as is the case in the common carburetor type.

The appended drawings show by way of example an embodiment of the invention. T he figure is a transverse section of a cylinder of the said sprayer and of the float chamber supplying the same.

Each cylinder 1 of the engine comprises the known inlet port 2, and exhaust port 3 which are opened at the end of the expansion stroke by the piston l whose closed end com* prises a deiiector 5, known per se; 6 is the ignition element, for example the usual sparking plug. A closed crank casev E constitutes a closed compression chamber 7 which communicates directly with the end of the cylinder opposite the woik chamber C.

According to our invention, an automatic valve 8 provides for an admission of air from the exterior into the crank case during the ascent of the piston, and a conduit 9 connects Nm- 1'9-5'344; and in- France April 7, 1924i the chamber 7 ofv thecrank case with tfhe- 55 work-chamber G ofithe cylinder,said conduit, being provided with suitable means for;v bringing thereiny the solid, liquid or. gaseous fuel. at. the moment when (the inlet port 25 being openedfby theA pistoni at the end; of; theA 50 down, stroke) thev air. which is compressed; in;

7i proeeedsinto the'work chamber: C throughi t'he'conduit 9.- Ai clos-ingdevice lllvfprovided@ with the control handle m serves to regulate the How section S between the conduit: 9fand 65 they inlet; port: 2;

Inftlie present example,y the liquid fuelz ils supplied by a sprayer 11 disposed; coaxially in the con-duit, 9; said; sprayen is suppliedI through the'conduit by the'float' chamberf 70 13-l which is. in. turni suppliech tihi'oughi the medium of; the: pipe 14 and. the: known auto?A matic needlevalve'15, by; thel fuel tankr. 16;: herein` the outlet; O of.v the sprayer opens`l within the closing `device 10 which has the 75 form of a hollow cock plug. Suitable piping 17, 17 connects the chamber 7 of the crank case E with the upper part of the tank 16 and with the top of the float chamber 13. In the form of construction herein repre- S0 sented, the sprayer 11 is of the single type, and the section of its outlet O may be adjusted by means of the rod 18 which is movable lengthwise by suitable controlling means, not shown. Obviously, we may em- 85 ploy any other type of simple or complex sprayer as desired.

The operation is as follows. After the eX- plosion and during the expansion stroke (down stroke), the piston compresses in the chamber 7 of the crank case the air which has been withdrawn through the valve8. Due to the piping 17 and 17', the fuel in the tank 16 and in the float chamber 13 will be placed in equilibrium, as to pressure, with the air surrounding the sprayer 11. /Vhen the piston is at the bottom of the stroke, t-he burnt gas is discharged through the port 3 in the known manner and the inlet port 2 willv now be opened; the air compressed in the chamber 7 will become charged with fuel as it flows around the outlet O of the sprayer, andthe. carburetted mixture will proceed through the port 2 into t-he work chamber C. The piston now rises, thus closing the poits 3 and 2, and it compresses the carburetted mixture in the chamber C in the known manner and withdraws fresh air through the valve 8 into the chamber 9, this air servingfor the supply of the cylinder during the succeeding stroke.

It should be observed that in this manner the explosive gas is formed only when it is admitted into the cylinder, and it will not enter the crank case, so that the several parts of the engine can be lubricated as in the four-stroke engines.

We will not depart from the principle of the invention by replacing the sprayer for the liquid fuel feed by other means suitably disposed for supplying a solid, liquid or gaseous fuel to the conduit 9, provided the fuel is supplied only while the air compressed in the crank case is flowing in the conduit 9 towards the cylinder C; nor will the said principle be departed from by modifying the throttle l() or by placing it in another position relatively to the means for feeding n the fuel. v

We claim:

l. A two-stroke internal combustion engine of the type set forth, in which the air is compressed in the crank case during the working stroke and, at the end of this stroke at the moment of the admission, passes from the crank case into the explosion chamber of the cylinder, comprising an air inlet automatic valve disposed to let enter the atmospheric air into the crank case during the return stroke, a fuel conduit leading from the fuel tank to the bottom of the float chamber, a conduit for equalizing thel pressure between the fuel tank and the float chamber, a conduit for equalizing the pressure between the crank case and the fuel tank, both said conduits for equalizing the pressures between the fuel tank and the float chamber and between the crank case and the fuel tank respectively being distinctly separate from each other, whereby the equilibrin um between said fuel tank and said float chamber is obtained.

2. A two-stroke internal combustion engine of the class described, comprisingan air inlet automatic valve disposed to let enter the atmospheric air into the crank case during the return stroke, a conduit leading fromthe crank case to the upper part of the fuel supply tank, a conduit leading from the fuel tank to the lower part of the float chamber to feed a spray nozzle provided between the crank case and the combustion chamber of the cylinder, and a conduit leading directly from the upper part of the fuel supplyl tank to the upper part of the lioatr chamber.

In testimony whereofI we have hereunto set our hands.

EMILE DUTEL. p JEAN MARC PERDONClNl. 

